Silicon based photodiodes provide spectral response in the visible wavelength range (VIS) but also in the near-infrared (NIR). For ambient light sensors (ALS) and image sensors with high color reproducibility the sensitivity in the NIR is unwanted as it impairs the sensing performance. Typically, external thin film filters are applied as near-infrared cut-off filters added to the photodiode or image sensor. We demonstrate plasmonic nanostructures fabricated directly within an extended CMOS (complementary metal–oxide–semiconductor) process. Designs in one and two metal layers are used and enable ambient light sensors as well as image sensors with pixel level NIR-blocking filters for color vision and additional NIR-sensitive pixels for simultaneous acquisition of VIS and NIR images.

High-end illumination devices based on LEDs require precise color matching, because the dominant wavelength depends
on temperature and changes due to aging. We demonstrate the performance of multispectral sensors fabricated using a
complementary metal-oxide semiconductor (CMOS) process for color-sensing feedback. Various plasmonic
nanostructures were simulated and implemented to achieve band pass and cut-off filters, placed on top of photodiodes.
These devices for multispectral sensing can be fabricated in high volume and measurements indicate that a wavelength
change of 3 nm yields a relative signal change of more than 20 % due to the steep-edge characteristics of the filters.

Sub-wavelength gratings and hole arrays in metal films are applicable for polarization and spectral selective sensors,
respectively. We demonstrate the fabrication of wire grid polarizers using standard complementary metal-oxide
semiconductor (CMOS) processes. Extraordinary optical transmission of hole arrays was achieved by using the
dedicated layer of a modified CMOS process. The structures were simulated using the finite-difference time-domain
(FDTD) method and fabricated using the work flow of integrated circuits. A high-speed polarization image sensor with a
pixel size of 6 μm was designed and demonstrated, and multispectral sensing was implemented using nanostructures
with different spectral filter performances on a single chip.

Sub-wavelength structures in metal films have interesting optical properties that can be implemented for sensing
applications: gratings act as wire grid polarizer, hole arrays with enhanced transmission can be used as spectral filters.
This paper demonstrates the feasibility of these nanostructures using 180 nm and 90 nm complementary metal-oxide
semiconductor (CMOS) processes. The metal layers of the process can be used for optical nanostructures with feature
sizes down to 100 nm. We describe the design and simulation of these metal structures using the finite-difference timedomain
(FDTD) method. The spectral response of the test structures was measured for different polarizations, where the
gratings showed typical features of wire grid polarizers. Using a 180 nm CMOS image sensor process, an image sensor
with 6 μm pixel size was designed and fabricated with different polarization selective structures allowing for polarization
imaging. A polarization camera using this image sensor is demonstrated, visualizing stress birefringence as an
application example. Finally, first results on the fabrication of hole arrays with a period of 320 nm are presented,
showing color filters with enhanced transmission.

The optical transmission of signals has several significant advantages like high transmission capacity, immunity from electromagnetic interference, and thin and low weight cables. Optical networks have a high potential for applications in buildings, but they will be widely used only if component and installation costs are reduced. One promising candidate especially for home networks is polymer optical fiber (POF) due to the low cost of the fiber and its installation, as well as significantly lower costs of all active and passive components compared to networks based on silica fibers. The present paper describes the properties of polymer optical fibers (POF), active and passive components developed in our institute for networks based on POF as well as different transmission experiments. The applications of these transmission systems for multimedia and multiservice networks are the distribution of video signals, the transmission of TV signals with carrier frequencies beyond the 3-dB bandwidth of POF, and a multimedia system for the transmission of video, audio, and data signals using wavelength division multiplexing (WDM).

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Journal of Applied Remote SensingJournal of Astronomical Telescopes Instruments and SystemsJournal of Biomedical OpticsJournal of Electronic ImagingJournal of Medical ImagingJournal of Micro/Nanolithography, MEMS, and MOEMSJournal of NanophotonicsJournal of Photonics for EnergyNeurophotonicsOptical EngineeringSPIE Reviews